ICECUBE是一种用于检测1 GEV和1 PEV之间大气和天体中微子的光学传感器的立方公斤阵列,该阵列已部署1.45 km至2.45 km的南极的冰盖表面以下1.45 km至2.45 km。来自ICE探测器的事件的分类和重建在ICeCube数据分析中起着核心作用。重建和分类事件是一个挑战,这是由于探测器的几何形状,不均匀的散射和冰中光的吸收,并且低于100 GEV的光,每个事件产生的信号光子数量相对较少。为了应对这一挑战,可以将ICECUBE事件表示为点云图形,并将图形神经网络(GNN)作为分类和重建方法。 GNN能够将中微子事件与宇宙射线背景区分开,对不同的中微子事件类型进行分类,并重建沉积的能量,方向和相互作用顶点。基于仿真,我们提供了1-100 GEV能量范围的比较与当前ICECUBE分析中使用的当前最新最大似然技术,包括已知系统不确定性的影响。对于中微子事件分类,与当前的IceCube方法相比,GNN以固定的假阳性速率(FPR)提高了信号效率的18%。另外,GNN在固定信号效率下将FPR的降低超过8(低于半百分比)。对于能源,方向和相互作用顶点的重建,与当前最大似然技术相比,分辨率平均提高了13%-20%。当在GPU上运行时,GNN能够以几乎是2.7 kHz的中位数ICECUBE触发速率的速率处理ICECUBE事件,这打开了在在线搜索瞬态事件中使用低能量中微子的可能性。
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本文研究了红外(IR)成像在乳房疾病检测中的潜在贡献。它比较了使用一些算法检测恶性乳房状况(例如支持向量机(SVM))在应用于公共数据时的一致性的结果。此外,为了利用实际IR成像的能力作为临床试验的补充,并使用高分辨率IR成像促进研究,我们认为使用了由自信训练的乳房医生修订的公共数据库是必不可少的。在我们的工作中,只有静态获取协议才被考虑。我们使用了来自Pro Engenharia(Proeng)公共数据库的LO2 IR单乳房图像(54个正常和48个发现)。这些图像是从联邦De Pernambuco大学(UFPE)大学医院收集的。我们采用了作者提出的相同功能,该功能使用顺序最小优化(SMO)分类器,获得了最佳结果,并获得了61.7%的准确性,而Youden指数为0.24。
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巴西最高法院每学期收到数万案件。法院员工花费数千个小时来执行这些案件的初步分析和分类 - 这需要努力从案件管理工作流的后部,更复杂的阶段进行努力。在本文中,我们探讨了来自巴西最高法院的文件多模式分类。我们在6,510起诉讼(339,478页)的新型多模式数据集上训练和评估我们的方法,并用手动注释将每个页面分配给六个类之一。每个诉讼都是页面的有序序列,它们既可以作为图像存储,又是通过光学特征识别提取的相应文本。我们首先训练两个单峰分类器:图像上对Imagenet进行了预先训练的重新编织,并且图像上进行了微调,并且具有多个内核尺寸过滤器的卷积网络在文档文本上从SCRATCH进行了训练。我们将它们用作视觉和文本特征的提取器,然后通过我们提出的融合模块组合。我们的融合模块可以通过使用学习的嵌入来处理缺失的文本或视觉输入,以获取缺少数据。此外,我们尝试使用双向长期记忆(BILSTM)网络和线性链条件随机字段进行实验,以模拟页面的顺序性质。多模式方法的表现都优于文本分类器和视觉分类器,尤其是在利用页面的顺序性质时。
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在许多实际应用程序中,强化学习(RL)代理可能必须解决多个任务,每个任务通常都是通过奖励功能建模的。如果奖励功能是线性表达的,并且代理商以前已经学会了一组针对不同任务的策略,则可以利用后继功能(SFS)来组合此类策略并确定有关新问题的合理解决方案。但是,确定的解决方案不能保证是最佳的。我们介绍了一种解决此限制的新颖算法。它允许RL代理结合现有政策并直接确定任意新问题的最佳政策,而无需与环境进行任何进一步的互动。我们首先(在轻度假设下)表明,SFS解决的转移学习问题等同于学习在RL中优化多个目标的学习问题。然后,我们引入了基于SF的乐观线性支持算法的扩展,以学习一组SFS构成凸面覆盖范围集的策略。我们证明,该集合中的策略可以通过广义策略改进组合,以构建任何可表达的新任务的最佳行为,而无需任何其他培训样本。我们从经验上表明,在价值函数近似下,我们的方法在离散和连续域中优于最先进的竞争算法。
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压力溃疡在ICU患者中具有很高的患病率,但如果以初始阶段识别,则可预防。在实践中,布拉登规模用于分类高风险患者。本文通过使用MIMIC-III V1.4中可用的数据调查了在电子健康中使用机器学习记录数据的使用。制定了两个主要贡献:评估考虑在住宿期间所有预测的模型的新方法,以及用于机器学习模型的新培训方法。结果与现有技术相比,表现出卓越的性能;此外,所有型号在精密召回曲线中的每个工作点都超过了Braden刻度。 - - les \〜oes por按\〜ao possuem alta preval \ ^ encia em pacientes de Uti e s \〜ao preven \'iveis ao serem endicidificadas em Est \'agios Iniciais。 na pr \'atica materiza-se a escala de braden para classifica \ c {c} \〜ao de pacientes em risco。 Este Artigo Investiga o Uso de Apenizado de M \'Aquina Em Dados de Registros Eletr \ ^ Onicos Para Este Fim,Parir Da Base dados Mimic-III V1.4。 s \〜ao feitas duas contribui \ c {c} \〜oes principais:uma nova abordagem para a avalia \ c {c} \〜ao dos modelos e da escala da escala de braden levando em conta todas作为predi \ c {c} \ 〜oes feitas ao longo das interna \ c {c} \〜oes,euro novo m \'etodo de treinamento para os modelos de aprendizo de m \'aquina。 os结果os overidos superam o estado da arte everifica-se que os modelos superam意义a escala de braden em todos oS pontos de Opera \ c {c} \〜〜ao da curva de precis \〜ao por sensibilidade。
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There are multiple scales of abstraction from which we can describe the same image, depending on whether we are focusing on fine-grained details or a more global attribute of the image. In brain mapping, learning to automatically parse images to build representations of both small-scale features (e.g., the presence of cells or blood vessels) and global properties of an image (e.g., which brain region the image comes from) is a crucial and open challenge. However, most existing datasets and benchmarks for neuroanatomy consider only a single downstream task at a time. To bridge this gap, we introduce a new dataset, annotations, and multiple downstream tasks that provide diverse ways to readout information about brain structure and architecture from the same image. Our multi-task neuroimaging benchmark (MTNeuro) is built on volumetric, micrometer-resolution X-ray microtomography images spanning a large thalamocortical section of mouse brain, encompassing multiple cortical and subcortical regions. We generated a number of different prediction challenges and evaluated several supervised and self-supervised models for brain-region prediction and pixel-level semantic segmentation of microstructures. Our experiments not only highlight the rich heterogeneity of this dataset, but also provide insights into how self-supervised approaches can be used to learn representations that capture multiple attributes of a single image and perform well on a variety of downstream tasks. Datasets, code, and pre-trained baseline models are provided at: https://mtneuro.github.io/ .
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The previous fine-grained datasets mainly focus on classification and are often captured in a controlled setup, with the camera focusing on the objects. We introduce the first Fine-Grained Vehicle Detection (FGVD) dataset in the wild, captured from a moving camera mounted on a car. It contains 5502 scene images with 210 unique fine-grained labels of multiple vehicle types organized in a three-level hierarchy. While previous classification datasets also include makes for different kinds of cars, the FGVD dataset introduces new class labels for categorizing two-wheelers, autorickshaws, and trucks. The FGVD dataset is challenging as it has vehicles in complex traffic scenarios with intra-class and inter-class variations in types, scale, pose, occlusion, and lighting conditions. The current object detectors like yolov5 and faster RCNN perform poorly on our dataset due to a lack of hierarchical modeling. Along with providing baseline results for existing object detectors on FGVD Dataset, we also present the results of a combination of an existing detector and the recent Hierarchical Residual Network (HRN) classifier for the FGVD task. Finally, we show that FGVD vehicle images are the most challenging to classify among the fine-grained datasets.
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Rigorous guarantees about the performance of predictive algorithms are necessary in order to ensure their responsible use. Previous work has largely focused on bounding the expected loss of a predictor, but this is not sufficient in many risk-sensitive applications where the distribution of errors is important. In this work, we propose a flexible framework to produce a family of bounds on quantiles of the loss distribution incurred by a predictor. Our method takes advantage of the order statistics of the observed loss values rather than relying on the sample mean alone. We show that a quantile is an informative way of quantifying predictive performance, and that our framework applies to a variety of quantile-based metrics, each targeting important subsets of the data distribution. We analyze the theoretical properties of our proposed method and demonstrate its ability to rigorously control loss quantiles on several real-world datasets.
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Traditionally, data analysis and theory have been viewed as separate disciplines, each feeding into fundamentally different types of models. Modern deep learning technology is beginning to unify these two disciplines and will produce a new class of predictively powerful space weather models that combine the physical insights gained by data and theory. We call on NASA to invest in the research and infrastructure necessary for the heliophysics' community to take advantage of these advances.
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In the Earth's magnetosphere, there are fewer than a dozen dedicated probes beyond low-Earth orbit making in-situ observations at any given time. As a result, we poorly understand its global structure and evolution, the mechanisms of its main activity processes, magnetic storms, and substorms. New Artificial Intelligence (AI) methods, including machine learning, data mining, and data assimilation, as well as new AI-enabled missions will need to be developed to meet this Sparse Data challenge.
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